<?php

/**
 * Simple filter to handle matching of multiple options selectable via checkboxes
 *
 * Definition items:
 * - numeric: If set to true, this item will use numeric operators instead of string.
 *
 */
class views_handler_filter_in_operator extends views_handler_filter {

    var $value_form_type = 'checkboxes';

    function construct() {
        parent::construct();
        $this->value_title = t('Options');
        $this->value_options = NULL;
    }

    /**
     * Child classes should be used to override this function and set the
     * 'value options', unless 'options callback' is defined as a valid function
     * or static public method to generate these values.
     *
     * This can use a guard to be used to reduce database hits as much as
     * possible.
     */
    function get_value_options() {
        if (isset($this->value_options)) {
            return;
        }

        if (isset($this->definition['options callback']) && is_callable($this->definition['options callback'])) {
            $this->value_options = call_user_func($this->definition['options callback']);
        } else {
            $this->value_options = array(t('Yes'), t('No'));
        }
    }

    function expose_options() {
        parent::expose_options();
        $this->options['expose']['reduce'] = FALSE;
    }

    function expose_form_right(&$form, &$form_state) {
        parent::expose_form_right($form, $form_state);
        $form['expose']['reduce'] = array(
            '#type' => 'checkbox',
            '#title' => t('Limit list to selected items'),
            '#description' => t('If checked, the only items presented to the user will be the ones selected here.'),
            '#default_value' => !empty($this->options['expose']['reduce']), // safety
        );
    }

    function option_definition() {
        $options = parent::option_definition();

        $options['operator']['default'] = 'in';
        $options['value']['default'] = array();

        return $options;
    }

    /**
     * This kind of construct makes it relatively easy for a child class
     * to add or remove functionality by overriding this function and
     * adding/removing items from this array.
     */
    function operators() {
        $operators = array(
            'in' => array(
                'title' => t('Is one of'),
                'short' => t('in'),
                'short_single' => t('='),
                'method' => 'op_simple',
                'values' => 1,
            ),
            'not in' => array(
                'title' => t('Is not one of'),
                'short' => t('not in'),
                'short_single' => t('<>'),
                'method' => 'op_simple',
                'values' => 1,
            ),
        );
        // if the definition allows for the empty operator, add it.
        if (!empty($this->definition['allow empty'])) {
            $operators += array(
                'empty' => array(
                    'title' => t('Is empty (NULL)'),
                    'method' => 'op_empty',
                    'short' => t('empty'),
                    'values' => 0,
                ),
                'not empty' => array(
                    'title' => t('Is not empty (NOT NULL)'),
                    'method' => 'op_empty',
                    'short' => t('not empty'),
                    'values' => 0,
                ),
            );
        }

        return $operators;
    }

    /**
     * Build strings from the operators() for 'select' options
     */
    function operator_options($which = 'title') {
        $options = array();
        foreach ($this->operators() as $id => $info) {
            $options[$id] = $info[$which];
        }

        return $options;
    }

    function operator_values($values = 1) {
        $options = array();
        foreach ($this->operators() as $id => $info) {
            if (isset($info['values']) && $info['values'] == $values) {
                $options[] = $id;
            }
        }

        return $options;
    }

    function value_form(&$form, &$form_state) {
        $form['value'] = array();

        $this->get_value_options();
        $options = $this->value_options;
        $default_value = (array) $this->value;

        $which = 'all';
        if (!empty($form['operator'])) {
            $source = ($form['operator']['#type'] == 'radios') ? 'radio:options[operator]' : 'edit-options-operator';
        }
        if (!empty($form_state['exposed'])) {
            $identifier = $this->options['expose']['identifier'];

            if (empty($this->options['expose']['use_operator']) || empty($this->options['expose']['operator'])) {
                // exposed and locked.
                $which = in_array($this->operator, $this->operator_values(1)) ? 'value' : 'none';
            } else {
                $source = 'edit-' . form_clean_id($this->options['expose']['operator']);
            }

            if (!empty($this->options['expose']['reduce'])) {
                $options = $this->reduce_value_options();

                if (empty($this->options['expose']['single']) && !empty($this->options['expose']['optional'])) {
                    $default_value = array();
                }
            }

            if (!empty($this->options['expose']['single'])) {
                if (!empty($this->options['expose']['optional']) && (empty($default_value) || !empty($this->options['expose']['reduce']))) {
                    $default_value = 'All';
                } else if (empty($default_value)) {
                    $keys = array_keys($options);
                    $default_value = array_shift($keys);
                } else {
                    $copy = $default_value;
                    $default_value = array_shift($copy);
                }
            }
        }

        if ($which == 'all' || $which == 'value') {
            $form['value'] = array(
                '#type' => $this->value_form_type,
                '#title' => $this->value_title,
                '#options' => $options,
                '#default_value' => $default_value,
                // These are only valid for 'select' type, but do no harm to checkboxes.
                '#multiple' => TRUE,
                '#size' => count($options) > 8 ? 8 : count($options),
            );
            if (!empty($form_state['exposed']) && !isset($form_state['input'][$identifier])) {
                $form_state['input'][$identifier] = $default_value;
            }

            $process = array();
            if ($this->value_form_type == 'checkboxes') {
                // If this form element will use checkboxes in the UI, we need to
                // check_plain() all the options ourselves since FAPI is inconsistent
                // about this. However, instead of directly doing that to the #options
                // right now, we define a #process callback since we might change our
                // mind later and convert this into a 'select' form element, which
                // would lead to double-escaping the options.
                $process[] = 'views_process_check_options';
            }
            if ($which == 'all') {
                if (empty($form_state['exposed']) && ($this->value_form_type == 'checkboxes' || $this->value_form_type == 'radios')) {
                    $process[] = "expand_$this->value_form_type";
                    $form['value']['#prefix'] = '<div id="edit-options-value-wrapper">';
                    $form['value']['#suffix'] = '</div>';
                }
                $process[] = 'views_process_dependency';
                $form['value']['#dependency'] = array($source => $this->operator_values(1));
            }
            if (!empty($process)) {
                $form['value']['#process'] = $process;
            }
        }
    }

    /**
     * When using exposed filters, we may be required to reduce the set.
     */
    function reduce_value_options($input = NULL) {
        if (!isset($input)) {
            $input = $this->value_options;
        }

        // Because options may be an array of strings, or an array of mixed arrays
        // and strings (optgroups) or an array of objects, we have to
        // step through and handle each one individually.
        $options = array();
        foreach ($input as $id => $option) {
            if (is_array($option)) {
                $options[$id] = $this->reduce_value_options($option);
                continue;
            } else if (is_object($option)) {
                $keys = array_keys($option->option);
                $key = array_shift($keys);
                if (isset($this->options['value'][$key])) {
                    $options[$id] = $option;
                }
            } else if (isset($this->options['value'][$id])) {
                $options[$id] = $option;
            }
        }
        return $options;
    }

    function accept_exposed_input($input) {
        // A very special override because the All state for this type of
        // filter could have a default:
        if (empty($this->options['exposed'])) {
            return TRUE;
        }

        // If this is single and optional, this says that yes this filter will
        // participate, but using the default settings, *if* 'limit is true.
        if (!empty($this->options['expose']['single']) && !empty($this->options['expose']['optional']) && !empty($this->options['expose']['limit'])) {
            $identifier = $this->options['expose']['identifier'];
            if ($input[$identifier] == 'All') {
                return TRUE;
            }
        }

        return parent::accept_exposed_input($input);
    }

    function value_submit($form, &$form_state) {
        // Drupal's FAPI system automatically puts '0' in for any checkbox that
        // was not set, and the key to the checkbox if it is set.
        // Unfortunately, this means that if the key to that checkbox is 0,
        // we are unable to tell if that checkbox was set or not.
        // Luckily, the '#value' on the checkboxes form actually contains
        // *only* a list of checkboxes that were set, and we can use that
        // instead.

        $form_state['values']['options']['value'] = $form['value']['#value'];
//    $form_state['values']['options']['value'] = array_filter($form_state['values']['options']['value']);
    }

    function admin_summary() {
        if (!empty($this->options['exposed'])) {
            return t('exposed');
        }
        $info = $this->operators();

        $this->get_value_options();

        if (!is_array($this->value)) {
            return;
        }

        $operator = check_plain($info[$this->operator]['short']);
        $values = '';
        if (in_array($this->operator, $this->operator_values(1))) {
            // Remove every element which is not known.
            foreach ($this->value as $value) {
                if (!isset($this->value_options[$value])) {
                    unset($this->value[$value]);
                }
            }
            // Choose different kind of ouput for 0, a single and multiple values.
            if (count($this->value) == 0) {
                $values = t('Unknown');
            } else if (count($this->value) == 1) {
                // If any, use the 'single' short name of the operator instead.
                if (isset($info[$this->operator]['short_single'])) {
                    $operator = check_plain($info[$this->operator]['short_single']);
                }

                $keys = $this->value;
                $value = array_shift($keys);
                $values = check_plain($this->value_options[$value]);
            } else {
                foreach ($this->value as $value) {
                    if ($values !== '') {
                        $values .= ', ';
                    }
                    if (strlen($values) > 8) {
                        $values .= '...';
                        break;
                    }
                    $values .= check_plain($this->value_options[$value]);
                }
            }
        }

        return $operator . (($values !== '') ? ' ' . $values : '');
    }

    function query() {
        $info = $this->operators();
        if (!empty($info[$this->operator]['method'])) {
            $this->{$info[$this->operator]['method']}();
        }
    }

    function op_simple() {
        if (empty($this->value)) {
            return;
        }
        $this->ensure_my_table();
        $placeholder = !empty($this->definition['numeric']) ? '%d' : "'%s'";

        $replace = array_fill(0, sizeof($this->value), $placeholder);
        $in = ' (' . implode(", ", $replace) . ')';

        // We use array_values() because the checkboxes keep keys and that can cause
        // array addition problems.
        $this->query->add_where($this->options['group'], "$this->table_alias.$this->real_field " . $this->operator . $in, array_values($this->value));
    }

    function op_empty() {
        $this->ensure_my_table();
        $field = "$this->table_alias.$this->real_field";

        if ($this->operator == 'empty') {
            $operator = "IS NULL";
        } else {
            $operator = "IS NOT NULL";
        }

        $this->query->add_where($this->options['group'], "$field $operator");
    }

}
